Shipping carton



A. J. PEZDEK SHIPPING CARTON Aug. 1, 1967 5 Sheets-Sheet 1 Filed July 23, 1965 A J. PEZDEK Aug. 1, 1967 SHIPPING CARTON 5 Sheets-Sheet 2 Filed July 23, 1965 A. J. PEZDEK SHIPPING CARTON Aug. 1, 1967 3 Sheets-Sheet 5 Filed July 23, 1965 [mi/275K 047% Mar dfiazaek, j" 4 United States Patent 3,333,635 SHIPPING CARTON Alexander J. Pezd'ek, Baltimore, Md, assignor to General Electric Company, a corporation of New York Filed July 23, 1965, Ser. No. 474,424 1 Claim. (Cl. 206-466) This invention relates to shipping cartons and more particularly to improvements in shipping cartons for porcelain suspension insulator strings.

A porcelain suspension insulator unit comprises a circular central piece of electrical grade porcelain to opposite ends of which are cemented metal hardware fittings. One fitting is a socket or clevis cap on what is usually called the top end and the other fitting is a complementary shaped ball or clevis pin on what is usually called the bottom end. A suspension insulator string consists of a plurality of suspension insulator units strung together by fitting the bottom pin into the top cap of adjacent units. Such strings are used for insulatingly supporting a transmission line conductor from a tower crossarm. The length of the string, and hence the number of units it contains is generally proportional to the voltage to ground of the line conductor.

It is the custom in the trade for the manufacturer of suspension insulator units to preassemble them into strings to meet the customers requirements and ship such preassembled strings rather than for the customer to assemble the strings from individually packaged and shipped units. As such strings are flexible, the porcelain frangible and subject to decrease in insulating strength due to surface contamination unless stored in a clean place, it is desirable to protect them for as long as possible with a strong container which will also have a good space factor for storage purposes.

It has been found that although a close fitting tubular container of circular cross section gives good support to the insulator string and results in low porcelain breakage when accidentally dropped on a hard surface it tends to roll like a log and thus creates a further hazard in being hard to handle and control. At the other extreme, a square cross section gives poor support and results in high porcelain breakage when dropped on one of its fiat sides because there is only a single line of support or contact for resisting impact between the circular porcelains and the bottom side of the container. Increasing the number of sides of a tubular or cylindrical container of regular polygonal cross section increases the impact strength and decreases porcelain breakage because there are a plurality of support points or lines for resisting impact in any direction, but for five, siX and seven sided polygons the space factor for storage is poor because with one side a horizontal bottom side there are no vertical flat sides so that space is wasted between horizontally adjacent cartons.

In accordance with the present invention, it has been found that a regular octagonal cross section gives the optimum combination of good space factor, low porcelain breakage of high impact strength, and resistance to rolling or ease of control and handling.

Another feature of the invention is the provision of open end pockets in the carton with reinforced sides for protecting the ends of the insulator string against accidental impacts While at the same time rendering them accessible from the outside so that, if desired, the insulator may be completely installed with the carton in place so as to protect and preserve the cleanliness of the insulator until the line is ready to be energized.

An object of the invention is to provide a new and improved shipping carton for suspension insulator strings.

Another object of the invention is to provide a shipping carton for insulator strings which has flat sides, good space factor, and high impact strength or low porcelain breakage under rough handling.

A further object of the invention is to provide a ship ping carton for insulator strings which can remain in place while the insulator is installed so as to afford maximum protection of the insulator string, and in addition keep the insulator string clean, eliminating the need for cleaning prior to energizing.

The invention will be better understood from the fol lowing description taken in connection with the accompanying drawings and its scope will be pointed out in the appended claims.

In the drawings,

FIG. 1 is a perspective view of a transmission line having suspension insulators enclosed in the shipping carton of the subject invention,

FIG. 2 is an enlarged perspective view partly in phantom of the shipping carton with an insulator string therein when viewed from the top end thereof,

FIG. 3 is a view similar to FIG. 2 of the bottom end,

FIG. 4 is a flat blank from which the top closure of the shipping carton is formed,

FIG. 5 is a view similar to FIG. 4 of the blank for forming the bottom closure,

FIG. 6 is a blank out of which the octagonal cross section tubular central portion of the shipping carton is formed,

FIG. 7 is a detailed perspective view of the octagonal shaped cylindrical central portion showing how the blank shown in FIG. 6 is folded and its ends overlapped to form the cylinder,

FIG. 8 is a view showing how a plurality of shipping cartons may be stacked or stored with good space factor,

FIG. 9 is an enlarged perspective view showing a modified way of installing an insulator which has been shipped in the shipping carton of the present invention,

FIG. 10 is a longitudinal sectional view of the shipping carton with an insulator string therein,

FIG. 11 is a perspective view of the formed bottom closure cup, and

FIG. 12 is a similar view of the top closure cup.

Referring now to the drawings and more particularly to FIG. 1, there is shown therein a transmission line tower 1 having crossarms 2 from which are suspended line conductors 3 by means of suspension insulator strings enclosed in shipping cartons 4.

FIG. 2 shows the carton 4 viewed from the top end in which the cap 5 of the top insulator of the enclosed string projects through the bottom 6 of a cup shaped closure member 7 having side portions 8 and 9 forming the rim thereof. The closure member 7 is plugged into an octagonal cross section cylindrical center member 10 extending the entire length of the carton.

FIG. 3 shows the pin 11 of the bottom insulator unit of the enclosed string protruding through a sunburst hole 12 in the bottom 13 of the bottom cup shaped closure member 14 having folded sides 15. The parts 7, 10 and 14 may be stamped from any suitable material such as corrugated paper board having a central corrugated layer bonded on the sides to smooth outer facings, or a hard fiber board. The wrapper part 10 which constitutes the central cylindrical portion is cut in the form of a rectangle and is scored with eight generally equally spaced parallel lines, as shown in FIG. 6, perpendicular to the flutes of the central corrugated portion so that it may be folded or bent along those lines with the two end panels overlapping as shown in FIG. 7. These overlapping portions may be fastened together by stapling or by means of a suitable adhesive or preferably by both means. It has been found that the strength and weathering characteristics of the carton are greatly improved if the corrugated board of the part 10 is wax impregnated, and in constructing this part the scoring of the fold lines shown in FIG. 6 should be done immediately after impregnating while the impregnant is still hot and malleable.

The top end closure piece 7 is stamped from generally similar material to that of the part 10, but it is not necessary to wax impregnate it. Because of the height of the cap of the insulator units, the depth of the top closure cup 7, which is shown in completed form in FIG. 12, is greater than the base of the individual radially extending flaps 8 and 9 which when bent form the rim side of the cup closure. Howevenit is not necessary to have all the flaps the same length and material can be saved by having alternate flaps shorter so that the blank 7 can be cut from a square whose sides are parallel to the ends of the short flaps 8. Such a square is smaller in area than a square whose sides would be parallel to the ends of the long flaps 9. The hole in the central bottom portion of the member 6 is of a size closely to embrace the sides 7 of the cup socket of the top insulator unit.

FIG. shows how the blank is cut for the bottom end closure 14. In this case, the rim flaps 15 are considerably shorter than their width or base so that there is no substantial saving of material in having the flaps of different length and they may be cut or punched from a square of unimpregnated paper board material whose sides are parallel to the ends of alternate flaps 15. The sunburst hole 12 in the center of the bottom portion 13 is provided so that the enlarged end of the pin 11 may pass therethrough and still have the sides of the holes 13 closely embrace the smaller diameter pin portion so as to centrally position the insulator string in the carton and close the bottom of the carton against the entry of dirt and contaminants.

When the flaps 8 and 9 of the top end closure cup of FIG. 4 are folded up, the top end closure plug has the shape shown in FIG. 12 and likewise when the flaps 15 of the bottom end closure cup are folded up, this element 14 has the shape shown in FIG. 11.

FIG. 8 shows how a plurality of the cartons 4 may be stacked for storage with flat sides adjacent each other so as to provide good space factor.

The end closures 7 and 14 when plugged into the central portion 10, with the hardware fittings 5 and 11 protruding through their respective openings, may be fastened in place in any suitable manner such as by staples 16.

It will be seen that by reason of the above construction the end hardware fittings are in open end pockets in the carton which are accessible from outside the carton while at the same time the insulator porcelains are entirely enclosed and protected from dirt. By reason of the accessibility of the hardware fittings, the insulator can be installed and attached at opposite ends to the usual crossarm fittings and conductor supporting saddles or yokes as indicated generally in FIG. 1 with the carton entirely intact. It will also be observed that these open end pockets have generally double thickness wall sides which comprise the outer octagonal wrapping and the rim flaps of the end closures, thus producing a reinforced construction for resisting impacts at the ends of the carton.

After the units are installed, the carton can easily be removed by cutting it away with a knife at which time it can simply be dropped to the ground, where by reason of its comparatively light weight and soft material, it will not damage parts on the ground such, for example, as exposed insulator porcelains. It can also be readily disposed of on the right of way by burning it.

Another way to install the insulator is shown in FIG. 9. In this case, circumferential cuts have been made in described the wrapper 10 inwardly of the end closures and the ends have been pulled off thus exposing one side of the end insulator porcelains, but the other octagonal wrapping 10 is left in place. The insulator is then installed in the usual manner and before the conductor is attached the wrapper 10 can merely be slid ed and thrown to the ground, or if the line conductor is attached to the bottom end of the conductor before the sheath 10 is removed, it can be slit with a knife and removed.

FIG. 10 is another view showing how the insulator string is supported in the sheath 10 by the end caps 7 and 14.

While there have been shown and described particular embodiments of the invention, it will be obvious to those skilled in the art that changes and modifications may be made without departing from the invention, and therefore it is intended by the appended claim to cover all such changes and modifications as fall within the true spirit and scope of the invention.

What I claim as new and desire to secure by Letters Patent of the United States is:

A shipping carton of a string of suspension insulator units of the type having a circular central porcelain ele ment with ball or clevis pin and socket or clevis cap hardware members attached to opposite ends thereof contained therein, said carton comprising an octagonal crosssection tubular central portion bounding an inscribed circle of substantially the same diameter as that of the porcelain element of the insulator, and octagonal crosssection cup-shaped closure plugs of unequal depth fitted into and respectively closing the opposite ends of said tubular central portion, the bottom portion of said deeper cup-shaped plug having a central opening embracing the sides of a ball or clevis pin hardware member and the bottom portion of said shallower cup-shaped plug having a central opening embracing the sides of a socket or clevis cap hardware member so that the outer ends of said hardware members extend through said openings, the rim portions of said cup-shaped plugs extending outwardly and terminating near the ends of said tubular central portionto forceable sides in said carton for access to said hardware members without opening said carton whereby said carton can remain in place to protect its enclosed suspension insulator string until after the insulator string is installed by connecting its end hardware members to an upper support and lower supported conductor respective ly, said deeper end closure plug having integral alternately long and short rectangular rim forming flaps extending from its eight sides, the relative length of said flaps being such that the ends of the short flaps lie on a straight line between adjacent corners of adjacent long flaps when'the central portion and the rim forming flaps are in a common plane. References Cited UNITED STATES PATENTS 1,581,921 4/ 1926 Doble 229-37X 2,100,773 11/ 1937 Boeye 229-5.7 2,349,020 5/1944 Throckmorton 229-37 X.

FOREIGN PATENTS 490,442 2/ 1953 Canada.

428,848 7/1911 France.

188,263 11/ 1922 Great Britain.

861,290 2/ 1961 Great Britain.

897,228 5/ 1962 Great Britain.

THERON E. CONDON, Primary Examiner.

I. M. CASKIE, Assistant Examiner.

provide open-end pockets with rein-. 

